Al''s water analogy..
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Posts: 46,084
Well, I am notoriously bad at "physical stuff" but what I was thinking of
would be a water hose. Consider that your water pressure literally comes
from a big tank of water now (that's why water towers are -- well -- towers
unless you live somewhere where they build them on a mountain or other
elevated area). When you use your garden hose, water comes out and that's
purely from the pressure of your city's water tower. If you occlude part of
the hose orifice, the pressure goes up dramatically.
Granted, I'm known to be "bad" at pretty much anything mechanical so I might
well be wrong, but it seems to me that the small hole will have more
pressure because it has less flow. Energy will be conserved so less flow
will turn into more pressure.
As for draining the tank (the other reply) I'm assuming a big enough tank
just as you don't plan for a battery draining to empty.
I'll be the first to say that these analogies are not perfect. If you really
want to get into the details of hydrodynamics, the flow is probably not
laminar which leads to other effects that make the analogy quite bad. Also,
the resistance of a pipe is not really linear over all possible flow rates.
Oh well, I don't want to get to far into water pipes because I don't know
much about it, but that's my take.
Al Williams
AWC
* Control 8 servos at once: http://www.al-williams.com/awce/pak8.htm
>
Original Message
> From: Chris Anderson [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=WY3R_m-nC9YeYZjRYOH3Kec8e7Vp2uEfk4LGIlOIvkVWEdjTr8OKxuq7BlZTpZlNc4wLVwzsEW0B]fes@g...[/url
> Sent: Thursday, May 03, 2001 8:12 AM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Re: Al's water analogy..
>
>
> Hey Al, Its my turn to be a smart-***.
>
> >If I punch a hole the size of my fist in the tank, more
> >water will flow per second, but it won't be under so much pressure
>
> Initially the pressure will be the same for both holes, as they would
> presumably be at the same depth from the surface of the water,
> the pressure
> will reduce faster for the larger hole.
>
> Sometimes water analogies can turn to rubbish, but like you said,
> if it gets
> some work done....
>
> Chris
>
>
>
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
would be a water hose. Consider that your water pressure literally comes
from a big tank of water now (that's why water towers are -- well -- towers
unless you live somewhere where they build them on a mountain or other
elevated area). When you use your garden hose, water comes out and that's
purely from the pressure of your city's water tower. If you occlude part of
the hose orifice, the pressure goes up dramatically.
Granted, I'm known to be "bad" at pretty much anything mechanical so I might
well be wrong, but it seems to me that the small hole will have more
pressure because it has less flow. Energy will be conserved so less flow
will turn into more pressure.
As for draining the tank (the other reply) I'm assuming a big enough tank
just as you don't plan for a battery draining to empty.
I'll be the first to say that these analogies are not perfect. If you really
want to get into the details of hydrodynamics, the flow is probably not
laminar which leads to other effects that make the analogy quite bad. Also,
the resistance of a pipe is not really linear over all possible flow rates.
Oh well, I don't want to get to far into water pipes because I don't know
much about it, but that's my take.
Al Williams
AWC
* Control 8 servos at once: http://www.al-williams.com/awce/pak8.htm
>
Original Message
> From: Chris Anderson [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=WY3R_m-nC9YeYZjRYOH3Kec8e7Vp2uEfk4LGIlOIvkVWEdjTr8OKxuq7BlZTpZlNc4wLVwzsEW0B]fes@g...[/url
> Sent: Thursday, May 03, 2001 8:12 AM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Re: Al's water analogy..
>
>
> Hey Al, Its my turn to be a smart-***.
>
> >If I punch a hole the size of my fist in the tank, more
> >water will flow per second, but it won't be under so much pressure
>
> Initially the pressure will be the same for both holes, as they would
> presumably be at the same depth from the surface of the water,
> the pressure
> will reduce faster for the larger hole.
>
> Sometimes water analogies can turn to rubbish, but like you said,
> if it gets
> some work done....
>
> Chris
>
>
>
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>